Phytochemical Composition and Invitro α- amylase Inhibition of Methanol Leaf Extract of Anarcadium Occidentales , Hunteria Umbellata, Parkia biglobosa, Psidium guajava and Vitellaria Paradoxa

Abstract

This study investigated both qualitative and quantitative phytoconstituents of the methanol leaf extracts of Anarcadium occidentales, Huntaria umbellata, parkia biglobosa, psidium guajava and vitellaria paradoxa and their inhibitory effect on α-amylase enzyme. Dinitrosalicylic (DNS) method was adopted for α-amylase inhibition assay while phytochemical screening was carried out on the extracts by standard methods. Preliminary qualitative pytochemical screening showed the presence of Anthraquinones, Flavonoids, Tannins, Steroids, Alkaloids, phenols, and Saponins in all the plant extracts, as well as reducing sugars with the exception of Hunteria umbellata extracts. Phlobatannins was not detected in all the plants extracts. The concentration of phenols ranges from 184.368±0.23 mg/g to 120.241±0.01 mg/g in Anacardium occidentales extract and Hunteria umbellata extract respectively. However, among the selected plants, Hunteria umbellata extract had the highest concentration of Alkaloids (76.76±0.01 mg/g) Parkia biglobosa extract had the highest tanins content (137.55±0.05 mg/g) and Vitellaria paradoxa extract contains more saponins (188.50±0.01 mg/g) as compared to other plant extracts Flavonoids concentration was higher in Parkia biglobosa extract (458.06±0.06 mg/g) while Psidium guajava extracts had (84.28±0.02 mg/g). The ability to inhibit α- amylase activity by the standard drug (Acarbose) and all the selected plant extracts increased as their concentration increases. Acarbose had a significant (p<0.05) higher activity than all the extracts with IC 50 of (76.34± 0.12 ug/ml). Anarcadium occidentales extract had a better activity and thus a lower IC 50 of (171.1±0.13 ug/ml) among all the plants while Hunteria umbellata extract had the least activity with IC 50 of (191.0 ± 0.12 ) However no significant (p<0.05) was observed when compared to the remaining extracts. This result suggests that the methanol leaf extract of the studied plants possesses some hypoglycemic potentials.